Evidence of two regimes of easterly waves over West Africa and the tropical Atlantic

被引:68
作者
Diedhiou, A [1 ]
Janicot, S [1 ]
Viltard, A [1 ]
de Felice, P [1 ]
机构
[1] Ecole Polytech, CNRS, Meteorol Dynam Lab, F-91128 Palaiseau, France
关键词
D O I
10.1029/98GL02152
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
Synoptic-scale easterly waves at 700 hPa have been studied over West Africa and the tropical Atlantic for the summers of 1979-1995. Spectral analyses (Fast Fourier and Wavelet Transforms) of 700 hPa meridional wind component along 17.5 degrees N enable to point out two band-periods, between 3 and 5 days and between 6 and 9 days. An example of each wave is shown. Composite analysis confirms the evidence of two such regimes of easterly waves during summer over West Africa and the tropical Atlantic. The 6-9-day wave regime differ from the 3-5-day wave regime by larger anticyclonic cells originated from the Libyan and the Azores areas, and by more northern tracks.
引用
收藏
页码:2805 / 2808
页数:4
相关论文
共 32 条
[11]  
CARLSON TN, 1969, MON WEATHER REV, V97, P256, DOI 10.1175/1520-0493(1969)097<0256:SHOTAD>2.3.CO
[12]  
2
[13]  
DEFELICE P, 1993, MON WEATHER REV, V121, P1291, DOI 10.1175/1520-0493(1993)121<1291:ASSWOD>2.0.CO
[14]  
2
[15]  
DEFELICE P, 1990, MON WEATHER REV, V118, P2624, DOI 10.1175/1520-0493(1990)118<2624:CONADW>2.0.CO
[16]  
2
[17]  
DHONNEUR G, 1974, THESIS DAKAR
[18]  
Kalnay E, 1996, B AM METEOROL SOC, V77, P437, DOI 10.1175/1520-0477(1996)077<0437:TNYRP>2.0.CO
[19]  
2
[20]  
KARYAMPUDI VM, 1988, J ATMOS SCI, V45, P3102, DOI 10.1175/1520-0469(1988)045<3102:AANSOT>2.0.CO